Martin Schwarzschild, the son of German astrophysicist Karl Schwarzschild, earned his Ph.D. at Göttingen. He left Germany in 1936, researched and taught at Oslo, Harvard, and Columbia, and, after serving in the U.S. Army in World War II, joined the faculty of Princeton University in 1947. His work on stellar structure and evolution led to improved understanding of pulsating stars, differential solar rotation, post-main sequence evolutionary tracks on the Hertzsprung-Russell diagram (including how stars become red giants), hydrogen shell sources, the helium flash, and the ages of star clusters. Much of this was done with R. Härm. Schwarzschild’s 1958 book, Structure and Evolution of the Stars, taught a generation of astrophysicists how to apply electronic computers to the computation of stellar models. In the 1950s and ’60s he headed the Stratoscope projects, which took instrumented balloons to unprecedented heights. The first Stratoscope produced high resolution images of solar granules and sunspots, confirming the existence of convection in the solar atmosphere, and the second obtained infrared spectra of planets, red giant stars, and the nuclei of galaxies. In his later years he made significant contributions toward understanding the dynamics of elliptical galaxies. Schwarzschild was renowned as a teacher and held major leadership positions in several scientific societies.